Coupling for hoses or the like

ABSTRACT

A coupling for connecting hoses to a medium under pressure includes a female part having a nipple release mechanism and at least one ball-type nipple locking member for initially locking a nipple in place within the female part, an axially displaceable valve member centrally located and movable in the female part from a closed position in contact with an annular valve seat and an open position away from the valve seat, a nipple insertable in the female part and having a groove in an outer surface region thereof adapted to initially engage the ball-type nipple locking member for locking the nipple in place in the female part upon insertion. The female part additionally includes an elongated rotatable arm having a rounded distal end for contacting the groove in the nipple for holding the nipple in place at an intermediate position consisting of a partial removal of the nipple from the female part upon subsequent activation of the nipple release mechanism until pressure inside the nipple drops below a predetermined pressure level.

This application is the national phase under 35 U.S.C. §371 of prior PCTInternationt Application No. PCT/SE97/00473 which has an Internationalfiling date of Mar. 20, 1997 which designated the United States ofAmerica, the entire contents of which are hereby incorporated byreference.

The invention relates to a couping for connecting hoses or the like fora medium under pressure in accordance with the preamble to claim 1.

Detachable couplings for connecting hoses or the like for pressure mediaare used extensively in industry and handicrafts, especially couplingsfor compressed air. Such couplings are often used for connecting acompressed air tool or the like to a compressed air source. The femalepart of the coupling has a valve element which makes it possible to keepthe hose leading to the female part continuously under pressure. Thenipple of the coupling is connected to a hose or the like which leads toa compressed air tool. When changing tools or detaching the tool fromthe compressed air source for some other reason, there is oftenrelatively high pressure there. When the nipple is disconnected from thefemale part, there is powerful recoil throwing the nipple in the hoseconnected thereto. There is also a loud noise at disconnection. Both therecoil force and the sound are disadvantages which should be removedfor,among other things, reasons of safety.

The purpose of the present invention is to achieve a coupling of thetype described by way of introduction which removes the above mentioneddisadvantages and makes possible disconnection of the nipple from thefemale part while the coupling is under pressure, without any recoil ornoise.

This is achieved according to the invention by means of a coupling whichis characterized by the features disclosed in the characterizing portionof claim 1.

Suitable embodiments of the coupling according to the invention aredisclosed in the subclaims.

The invention will be described in more detail below with reference tothe accompanying drawing, in which

FIG. 1 shows a longitudinal section through a coupling according to oneembodiment of the invention in its connected state,

FIG. 2 shows the coupling according to FIG. 1 at the beginning of thedisconnecting process,

FIG. 3 shows the coupling of FIGS. 1 and 2 in an intermediate positionduring a disconnecting process, and

FIG. 4 shows the female part of the coupling shown in FIGS. 1-3 afterdisconnection of the nipple.

The coupling shown in the drawing comprises a female part 1 and a nipple2 insertable therein. The female part 1 is provided with an attachmentmeans 3 for a hose or a pipe, and the nipple 2 is provided withattachment means 4 for insertion into a hose. The female part 1 isintended to be connected to a pressure medium source (not shown) whilethe nipple 2 is intended to be connected via hose to a tool or the like(not shown).

A ball lock means of a type known per se with a number of balls 5distributed about the periphery and disposed in radial openings in thefemale part 1 and cooperating with a circumferential groove 6 in thenipple, is arranged in the vicinity of the free end of the female part1. The functioning of this ball lock means is well known and the balllock means is used to lock the nipple 2 in its inserted position in thefemale part 1, as shown in FIG. 1. The balls 5 are kept pressed into thegroove 6 by means of a ring 7, which is axially movable along theoutside of the female part 1 and which is biased by means of a spring 8towards the locking position shown in FIG. 1.

The nipple 2 is hollow and keeps a valve element 9, in the positionshown in FIG. 1, spaced from a valve seat 10 within the female part 1.The valve element 9 is provided for this purpose with an elongatedhollow extension member 11 which is provided with radial openings 11′adjacent the valve element proper 9 to make possible flow of mediumthrough the coupling. In this position shown in FIG. 1, the nipple 2.via the elongated extension member 11 has moved the valve body 9 awayfrom the valve seat 10, by compressing a spring 12.

The extension member 11 is provided at its buter surface with aperipheral groove 13, into which there extends a shoulder 14 at one endof an arm 15. The drawing shows only one arm 15, but in practice thefemale part 1 is provided with a plurality of such arms spacedcircumferentially. At the end of the arm 15 remote from the shoulder 14there is a rounded projection 16, which in the engaged position shown inFIG. 1 extends into the groove 6 in the nipple 2.

In the position shown in FIG. 2, a disengaging process has just began. Asleeve 17, which is biased by a spring 18 to the coupled position shownin FIG. 1. has been moved away from the free position of the female part1. The ring 7 has followed the sleeve 17 against the force of its spring8, so that a a bevelled end of the ring 7 cooperates with the balls 5.In this position, the balls 5 can move radially outwards and thus pressthe ring 7 further backwards against the force of the spring 8. Aprojection 19 on the sleeve 17 abuts against the radially outer surfaceof the arm 15 and keeps it in engagement with the groove 6 in the nipple2.

When the nipple 2, as a result of the force of the spring 12 is pressedby the elongated extension member 11 of the valve element 9, axially outof the female part 1, the balls 5 will be pressed radially outwards fromthe groove 6 by virtue of the fact that the edges of the groove 6 areoblique. The nipple 2 is thereby freed to move axially out of the femalepart 1 until it reaches the position shown in FIG. 3. In this positionthe valve element 9 has been moved into sealing engagement with thevalve seat 10, so that no flow of medium is possible through the femalepart 1. The arm 15 is however, retained with its projection 16 extendinginto the groove 6 because the projection 19 on the sleeve 17 will notpermit the arm 15 and its projection 16 to move radially outwards. Thenipple 2 is thus held in an intermediate position. Pressure medium inthe nipple 2 and in the hose connected thereto can thus exit through thegap 12′ between the extension member 11 of the valve element 9 and thefemale part 1 into the surroundings. The pressure in the nipple 2providing the axial force on the nipple 2 away from the female part 1drops of course. This force exerts a radially outwardly directed forceon the projection 16 and the arm 15. The arm 15 is provided with adepression 20 with oblique edges, into which the projection 19 of thesleeve 17 extends. The radially outwardly directed force on the arm 15holds the sleeve 17 in the position shown in FIG. 3 until the internalpressure in the nipple 2 has dropped to a predetermined level. When thislevel has been passed, the force on the spring 18 will overcome theradially outwardly directed force on the arm 15, so that the projection19 can be moved out of the depression 20. The spring 18 can thereafterdisplace the sleeve 17 to the position shown in FIG. 4, in which the arm15 can pivot radially outwards to thus free the nipple 2 for removalfrom the female part 1.

The process described above enables the nipple 2 to be removed from thefemale part 1 in a controlled and satisfactory manner even if theinterim pressure in the coupling is relatively high. In summary, it canbe said that the nipple 2 is first moved to an intermediate positionpartial removal as shown in FIG. 3, in which the valve element 9 sealsagainst the valve seat 10, whereafter the internal pressure on thenipple 2 and the portions connected thereto will be allowed to drop in acontrolled manner by releasing to the surroundings via the gap 12′. Whenthe internal pressure has dropped to a certain level pressure, which canbe determined by suitable dimensioning of the components, the nipple 2is released for complete removal from the female part 1 when the arm 15pivots outwardly from the nipple groove. In this manner, both noiseandthe powerful recoil are avoided, which means that the disengagementcan be done in a satisfactory manner as regards safety and convenience.

The invention is of course not limited to the embodiment describedabove. However, it can be modified within the scope of the attachedpatent claims.

What is claimed is:
 1. A coupling for connecting hoses or the like to amedium under pressure, comprising: a female part including a nipplerelease mechanism and at least one ball-type nipple locking member forinitially locking a nipple in place within the female part; an axiallydisplaceable valve member centrally located and movable in the femalepart from a closed position in contact with an annular valve seat and anopen position away from the valve seat; and, a nipple insertable in thefemale part and including an outer surface region adapted to initiallyengage the ball-type nipple locking member for locking the nipple inplace in the female part upon insertion; said female part additionallyincluding a restraining member for holding the nipple in place at anintermediate position consisting of a partial removal of the nipple fromthe female part upon subsequent activation of the nipple releasemechanism together with movement of the valve member to the closedposition against the valve seat and thereafter releasing the nipple forcomplete removal from the female part in response to pressure inside thenipple dropping below a predetermined pressure level.
 2. A couplingaccording to claim 1 wherein said valve member is biased so as to be inthe closed position in absence of the nipple or the removal thereof fromthe female part.
 3. A coupling according to claim 2 wherein saidball-type nipple locking member comprises a ball member and said surfaceregion of said nipple comprises a groove formed in an outer surface ofthe nipple for receiving said ball member.
 4. A coupling according toclaim 3 wherein said nipple release mechanism comprises a slideable bodymember located on an outer portion of the female part and providing anaccess opening adjacent the ball member when actuated for receiving theball member so as to permit removal of the nipple from the female partupon a subsequent release thereof by said restraining member.
 5. Acoupling according to claim 4 wherein said nipple release mechanismcomprises a spring loaded slideable sleeve assembly which restrains theball member so as to be in contact with said surface region of thenipple in absence of an actuation of the nipple release mechanism.
 6. Acoupling according to claim 5 wherein said restraining member comprisesan elongated rotatable arm mounted on the female part and locatedbeneath the slideable sleeve assembly, and having a rounded distal endportion of a size corresponding to the ball member for contacting saidgroove in the nipple.
 7. A coupling according to claim 6 wherein saidarm includes a depressed region on an outer surface adjacent the roundedend portion and said sleeve assembly includes an inwardly facingprojection in an outer end portion thereof for engaging the depressedregion of the arm when the sleeve assembly is manually moved in an axialdirection and thereby temporarily locking the nipple in place, andthereafter becoming disengaged upon release of the sleeve assembly so asto allow the rounded end portion of the arm to move out of the groove inthe surface region of the nipple when the pressure drops below saidpredetermined level.
 8. A coupling according to claim 1 and additionallyincluding a bias spring member located between the valve member and thefemale part for biasing the valve member to the closed position inabsence of the nipple or the removal thereof from the female part butpermitting the valve member to move to the open position upon theinsertion of the nipple in the female part.
 9. A coupling for connectinghoses or the like to a medium under pressure, comprising: a female partincluding a nipple release mechanism and at least one ball-type nipplelocking member for initially locking a nipple in place within the femalepart; an axially displaceable valve member centrally located and movablein the female part from a closed position in contact with an annularvalve seat and an open position away from the valve seat; and, a nippleinsertable in the female part and including a groove in an outer surfaceregion adapted to initially engage the ball-type nipple locking memberfor locking the nipple in place in the female part upon insertion; saidfemale part additionally including a restraining member for holding thenipple in place at an intermediate position consisting of a partialremoval of the nipple from the female part upon subsequent activation ofthe nipple release mechanism together with movement of the valve memberto the closed position against the valve seat and thereafter releasingthe nipple for complete removal from the female part in response topressure inside the nipple dropping below a predetermined pressurelevel; and wherein said restraining member comprises an elongatedrotatable arm mounted on the female part and located beneath theslideable sleeve assembly, and having a rounded distal end portion of asize corresponding to the ball member for contacting said groove in thenipple.
 10. A coupling for connecting hoses or the like to a mediumunder pressure, comprising: a female part including a nipple releasemechanism and at least one ball-type nipple locking member for initiallylocking a nipple in place within the female part; an axiallydisplaceable valve member centrally located and movable in the femalepart from a closed position in contact with an annular valve seat and anopen position away from the valve seat; and, a nipple insertable in thefemale part and including an outer surface region adapted to initiallyengage the ball-type nipple locking member for locking the nipple inplace in the female part upon insertion; said female part additionallyincluding a restraining member for holding the nipple in place at anintermediate position consisting of a partial removal of the nipple fromthe female part upon subsequent activation of the nipple releasemechanism together with movement of the valve member to the closedposition against the valve seat and thereafter releasing the nipple forcomplete removal from the female part in response to pressure inside thenipple dropping below a predetermined pressure level; wherein saidball-type nipple locking member comprises a ball member and said surfaceregion of said nipple comprises a groove formed in an outer surface ofthe nipple for receiving said ball member; and wherein said nipplerelease mechanism comprises a slideable body member located on an outerportion of the female part and providing an access opening adjacent theball member when actuated for receiving the ball member so as to permitremoval of the nipple from the female part upon a subsequent releasethereof by said restraining member.